Waste Water Solution in China

Overview

A complete wastewater treatment plant for a multinational pharmaceutical plant in Taizhou, Zhejiang Province, China was completed in December 2012.

Challenge

Membracon made a site visit and discussed with the customer the issues that they were having. Following the Membracon proposed a new 16.8m3hr Reverse Osmosis System with the correct pretreatment dosing system to optimise performance. Membracon also added the option to transfer pure water to the existing tanks to enable the existing temperamental system to become redundant. We also worked with the customer to assist in their ESG goals and proposed an energy efficient system with variable speed drives.

Solution

The retrofit solution makes use of the existing concrete tanks together with anaerobic pre-treatment with a UASB (Valorsabio UASB-PRO), implemented in November 2011, and aerobic treatment based on Valorsabio’s Jet-Loop System©. Membrane separation is based on Shanghai MegaVision FMBR-1.0-100 FS membrane panels. These are arranged in 12 modules containing 100 x 1 m² panels (and thus a flux of around 14 LMH at the flow of 400 m³/day) divided between 2 tanks. Further clarification by chemical coagulation/flocculation has been installed to remove non-biodegradable substances.

Results

The UASB-PRO employs a new pulse process for the wastewater feed which addresses issues sometimes encountered in large UASBs relating to unbalanced feed distribution, short-circuiting inside the bioreactors and difficulties in stabilising the up-flow of wastewater within the design range. The anaerobic treatment reduces the COD loads by up to more than 85%, generating biogas which offsets the operating cost by its use for water heating. The aerobic process operates at an HRT of less than 25% of the previously installed conventional activated sludge process. The COD is reduced from 1,300- 1,400 to 600-800 mg/L.